TOKYO — Japan on Friday voiced concern over the rise of the yen to fresh 15-year highs against the dollar and signalled it was ready to wade back into markets to intervene amid fears of a global devaluation battle.

“I am very concerned about the current situation,” Prime Minister Naoto Kan told parliament when asked about the yen’s strength, which puts Japan’s growth-driving exporters at a disadvantage by making their products more expensive overseas.

“We will take decisive steps when necessary, from the perspective of curbing excessive fluctuations in exchange rates,” Finance Minister Yoshihiko Noda told a regular press conference.

Amid expectations the US Federal Reserve will adopt further easing measures to pump more liquidity into the world’s largest economy and further weaken the dollar, the unit Thursday plunged to fresh 15-year lows against the yen.

A surprise policy tightening move by Singaporean authorities to widen the trading band of its currency on Thursday also added to pressure on the greenback and pushed the Singaporean unit to record highs.

On Friday the dollar stood at 81.42 yen, little changed from 81.44 in New York Thursday, after the unit earlier plunged to a 15-year low of 80.89 yen.